Outdoor switch contact



March 14, 1933- G. A. MATTHEWS 1,901,607

OUTDOOR SWITCH CONTACT Original Filed Jan. 18, 1929 ATTORNEYS Fatented Mar. 14, 1933;

UNITED STATES PATIENT OFFICE."

GEORGE ;A.- MATTHEWS, OF DETROIT, MICHIGAN, ASSIG-NOR T0 WESTINGHOUSE ELECTRIC 85 MANUFAC'FURINGCOMPANY, OF. JPITTSBURGH, PENNSYLVANIA oU'rnoon SWITCH CONTACT Original application filed January 18, 1929, Serial No. 333,362. Divided and. this application filed May 31,

1930. Serial No. 458,862. 1

This invention relates to mechanism for afi'ording and maintaining a high degree of etticiency in the contact surfaces of outdoor electrical circuit switches, and has for its object an improved organization of parts, each operation of which, closure or opening, involves such a scraping or sliding movement of the parts relative to one another as will act to break up any corrosive accumulation. or similar deposit upon the surface of the parts thus brought into contact which might otherwise impair eflective electrical contact between the surfaces and which will at the same time permit the easy opening and closing of the switch parts without undue mechanical resistance.

Since such mechanisms are generally mounted upon exposed poles or other structural supports, without protection against sleet and similar weather conditions, itis obvious that the parts of such a mechanism must be so arranged and correlated that not only will they function positively and reliably as ,regards the movement of the terminals into and out of contact with one another, but as well that such movement most of itself and automatically revolve and effect such a scraping or rubbing movement of the parts as has been above remarked upon, and for many uses this in turn makes 1t advisableto so position the last one of the contact parts that its intendedly exposed surface will face downwardly, thus being protected from the weather in the same manner that the underside of a roof of an otherwise open structure would be at least partially'sheltered.

In view of the diverse constructions for eifecting these desired proportions shown in my now pending application Serial No. 833,- 362, filed January 18, 1929, it has seemed advisable to make the subject matter of certain of the constructions therein shown the subject of this separate and consequently divisional application.

In the drawing:

Figure 1 is a side elevational View of a preferred form of disconnecting switch peculiarly adapted to use cooperatively with the relatively fixed contact members whose engaging end of the U shaped springL is in section of one of the relatively fixed contact members with the'contact arm from the swinging switch piece shown in initial operative relation thereto.

Figure 3 is a'view similar to Figure 2 showing the parts in an intermediate stage of'operati've movement relatively to one another. W Figure 4 is a similar view showing the parts in fully contacting positions. A indicates a suitable supporting struc--' ture, such as a channel bar, whereon are mounted three insulators, as B, C, and D, the center insulator G-carrying an axially rotatable rod 13 whereon is mounted. the switch arm F, which is preferably tubular and has at each end a'contact finger G carried on the pin or rod H in a way to be capable of limited rotative movement with respect to the tubular part F. A coil spring J. positioned in thegcenterportion of the tubu lar swinging arm F acts to pull each contact finger to-the relatively depressed position shown 1n-Figure 2, this being the normal inoperative position thereof. The coil spring J is connected to each finger by a rod K, the outer portion of which fits into a socket K on the outer end of the tube, and this socket may be utilized, when the parts carried by the tubeF are being assembled, as a hold for a wrench or similar turning instrument, for the purpose of providing such initial tention upon the spring J as may beneeded.

Each one of the outer insulators B and D carries a horseshoe: or U-shaped spring L, one leg of which is suitably attached to the insulator, whilethe'otherleg extends thereover and adjacent the contact fi'ngefG already remarked upon as supported by the tubular swingingarm F. Upon the overpreferably bolted or similarly secure d an initially separate contact plate M, whose surface is adapted to be wipinglyengagedby the end of the contact finger Gas the arm F is swung, so thatthe terminals of each of 1 0' I $preciably separated from the hub or inner the fingers G can thus engage such part of its corresponding one of the relatively fixed contact elements L. The ends of each of the contact pieces G initially engage the depend ing abutment part N as shown in Figure 2, but as the closingmovement of the switch continues, the end of the finger G moves upwardly along the left-hand surface of the abutment N as viewed in Figures 2, 3, and 4 against the resistance of the spring J within the arm F, and soon strikes the, contact plate M alreadyv mentioned, along which it wipingl-y moves, thus forcing the top or freely swinging leg of the U-shaped part L upward. In the position shown in Figure 3 this described movement is just about to. begin, the end of the contact finger G resting in an angle bounded by the contact plate M and the surface of the abutment N. The continued turning of the contact finger about the axis of the swinging arm F as acenter of movement effects a sort of knuckle turning of the. rounded end thereof along and relatively to these surfaces. The thus positively induced movement thereof is yieldingly opfrom the initial or .unactuated position compare Figures 2 and 4-so that the terminal projection P on thelower end of the web of the plate M, of which the abutment N is also a part and which initially is quite apend of the contact piece G, is constantly swung toward the position of contact, shown in Figure 4; a comparison'of the positions of these parts as shown in Figure 2 and in .--Figure 4: will show that the attainment by the end ofthe contact piece G of this last describedposition has involved its swing past its dead center, measured along the axial length of the piece G, thus resiliently though the then attained position.

When the parts have been thus swung and their relativemovement effected in the manner indicated, not only has a wiping or scrap "ing movement of the downwardly facing surface of the part M' been accomplished, but also a scraping or rubbing of the rounded end of'theswinging contact finger G as well, due to the resiliencyof the fixed abutment member L. The final position attained by these parts and indicated in Figure 4 causes a continued compressive straln which holds the parts firmly in desired; relation and against undesired displacement during the "time that the closure position of the switch tween the two legs of the latter and provided adequate space for the swing of the contact finger, regardless of what accumulation of ice or sleet may have taken place on the lower leg of the spring or upon the top of its supportinginsulating cap B or D. All of the engaged contact surfaces of the parts M and N being presented downwardly for the action of the contact finger against them, are

protected amply by-the skirtingor shell formation indicated at Q which thus acts as a lateral protection against horizontally driven sleet or ice particles.

It will of course be obvious that variant structural forms of the swinging tubular arm and its supported'parts may be resorted to, without departure from the fair an intended spirit of this disclosure, the. central feature of which is the downwardly facing or roofprotected positioning of the contact surfaces. which are designed to. be scraped or cleared by the rubbing of the rounded endofrthe contact arm GT, including as well, the beneficial structural features made possible by the contouring and positioning of the re-v silient uesha'ped element L as. a Whole.

Whatlclaini'is:

1. Ina switclna rotatably mountedrigid arm carrying a conductor pivoted on the end thereof, a yieldabl-y mounted conductor-10s cated at a suitable point for contact against a downwardly-facing surface thereof by the conductor on the end of said arm upon rota-i tion thereof, furth er rotation of said arm rota-ting said pivotally mounted conductor against yielding pressure of the mounting for said other conductoriwhereby extraneous matter is ground away andproper electrical contact; established, said pivoted conductor upon said arm swinging past the vertical line through the points of contact upon said yieldably mounted conductor, whereby said yielding means tendsto continue rotation of said arm, and a stop. for, said arm immedi-, ately beyond said vertical line whereby a {locking means is, provided for said cone ductor.

2. In, a switch, a rotatablymounted rigid, arm carrying a conductor pivotally mountedon the end thereof, a second conductor yieldably mounted at a suitable distance for contactby said first named conductor, a; shroud for said second conductor comprising a, roof, sidewalls and a back plate angularly disposed to said conductor, said pivotally mounted conductor upon rota-tion"of'said arm sliding along said back plate upon ape proaching said second conductor, said second conductor and said shroud yielding againstfurther rotation of said arm aftercontact of said conductors, said pivoted conductor rotatingagainst said shrouded conductor during yielding of said shrouded conductor whereby a proper electrical contact is insured,

said yielding meanstendingeto continue rotation of said arm as the pivot of said first conductor passes the dead center line through the points of contact with said shrouded conductor, and a stop beyond said dead center line whereby said arm is maintained against said stop by said yielding means, and whereby contact between said conductors is maintained.

3. In a switch, a plurality of conductors, one of said conductors being swingable to establish a line contact with the other of said conductors which latter though limitedly resilientis fixed in location, further movement of said swingable conductor rotating the contacting end thereof against a downwardly-facing surface on saidsecond conductor whereby the surfaces of said conductors frictionally grind away all extraneous matter therebetween to establish a good electrical connection, and a stop for limiting the throw of the first named of said conductors in such contacting position.

4. In a switch, a plurality of conductors, one of said conductors being fixedly positioned though slightly yieldable, the other of said conductors being pivotally mounted on an arm, a spring in said arm connected to said pivoted conductor, rotation of said arm establishing a line contact between said pivotally mounted conductor and said last named conductor, further rotation of said arm rotating the end of said pivotally mounted conductor against and along a downwardly facing surface upon said other conductor and against torsion of said spring whereby a gradually increasing pressure is exerted between said surfaces, and a stop for maintaining the contact established between the surfaces of said conductors after said firstnamed conductor has passed the point of maximum frictional engagement against said second contact.

5. In a switch, in combination with a rotatably mounted rigid arm provided with terminally located conductor elements, a pair of cooperable conductor elements positioned at points suitable for engagement by the terminal elements on said rigid arm when the latter is swung to position of engagement with said last named conductor elements, each of said latter comprising a slightly resilient member of generally U-shaped contour, an anchored insulating support to which one leg of said U-shaped member is attached, and a supplemental piece fixed to the other leg of the U-shaped member in position to present a downwardly facing contact against which the end of the adjacent terminal conductor element on said rigid arm wipingly engages as the latter is rotatively actuated, thereby flexing the supporting U-shaped member to a degree suflicient to throw into engagement with its adjacent terminal conductor element a projecting stop portion of said supplemental piece which is normally.

out of contact therewith.

6. In combinationwith a relatively rigid ingsaid rigid arm in position of possible swing in a substantiallyhorizontal plane, and

a pair of insulatedly supported fixed thou-gh:

slightlyresi-lient contact members adapted to be engaged'by their adjacent rotatable con-.

tact members onsaid rigid arm when the lat- '1 ter is suitably actuated, each ofsaid fixed con.- I

tact members being of'substantially U-shaped.

contour and carrying on one branch a downwardly facing preparedsurfaceagainst one portion-of which the end of its corresponding rotatable contact member is adapted to wip- 'f inglyf engage, and with which another portion of said resilientcontact member is adapt ed to be brought into engagementupon the completion of thewiping movement of its rotatable contact member.relatively thereto,

after overcomingthe resistance of the fixed though resilient contact member to the prog' I ress of said'wiping movement.-.

7. A switch, comprising, in combination with a rotatably supported swinging arm, and a relatively movable contact member carried on each end of said swinging arm, a pair of fixed though adequately resilient contact elements located in positions of potential con tact by the contact members on said swinging arm, each comprising an insulatedly supported U-shaped member and a downwardly facing supplemental piece carried on one branch of said U-shaped member, against a selected portion of which the corresponding contact member on said swinging armis adapted to wipingly engage against the resilient resistance thereto afforded by said U-shaped member, and by anormally spaced portion of which latter a portion of the corresponding contact member on said swinging arm is.

adapted to be engaged upon the completion of its described wiping contact movement.

8. In a switch, in combination with a relatively rigid arm supported in position of potential swinging movement in a horizontal lane, and relatively movable contact memers carried on the ends of said arm, fixedly positioned contact pieces adapted to be engaged by said relatively movable contact members when said arm is appropriately swung, each comprising an insulatedly supported and slightly resilient U-shaped member, and a supplemental contact piece supported thereby in downwardly facing position, adapted to be wipingly engaged by its corresponding movable contact member on said swinging arm, and such supplemental piece having a projection which thoughinitially out of engagement with its correspond- 7 ing movable contact member on said swinging arm is lockingly brought into engagement therewith at theend of the wiping movement of the latter along the downwardly facing surfaceof such supplemental .piece. I 9.In a switch, the combination, with a horizontally swingable and relatively rigid 'arm provided with relatively movable confactpieces at the ends thereof, of fixedly located U-shaped contact elements adapted to beengaged by said relatively movable contact pieces upon the appropriate swing of said relatively rigid arm, one branch of each of said U shaped contact elements being pro vided with a downwardly facing contactsurface adapted to be wipingly engaged by its corresponding movable contact pieceon said swinging arm and to thereafter lockingly en gage the latter with a projecting branch thereof after the described swinging movement of its movable contact piece on the rigid 29 arm has passed the line of maximum resilient opposition to its wiping travel along said downwardly facing contact surface. f In testimony whereof I sign this specifica- .1on.

GEORGE A. MATTHEWS. 

